Adjustable stool or chair



H. SHAW.

ADJUSTABLE STOOL 0R CHAIR.

APPLICATION FILED APR.21. 1920.

1 ,$357,825. Patented Nov. 2, 1920.

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PATENT OFFICE.

HARRY SHAW, 0F CHICAGO, ILLINOIS.

ADJUSTABLE sTooL on CHAIR.

Application filed April 21, 1920.

To ZZ whom t lmay con/cern.'

Be it known that l, HARRY SHAW, a citizen of the United States, residing at Chicago, Illinois, have invented certain new and useful Improvements in idjustable Stools or Chairs; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to malte and use the same.

l/ly invention relates to stools or chairs o and in one of its general aspects aims to provide simple, strong and easily manipulated means for varying the height o f the seat at the pleasure of the user. More particularly. my invention aims to provide a construction for this purpose which will freely permit the rotating of the seat, which will enable the seat to be raised to any extent within the limits of the construction by freely lifting the seat and the parts attached thereto, and in which the seat can readily loe lowered to any desired extent upon the pressing of an easily reached push button. Furthermore, my invention aims to provide a construction for this purpose in which the elements for latching the stem of the seat inany desired position are cheaply constructed and easily assembled, and in which certain parts of the mechanism will readily prevent other parts from unscrewing or shifting in their operative relations.

In another aspect, my invention aims to provide a simple substitute for the cast spiders heretofore used in connection with swivel chair constructions, and to provide this substitute in such a manner that it can easily and cheaply be constructed out of bar steel, and so that it will be arranged both for unusual strength andfor a desir'- able distribution of the strains. Still further and more detailed objects will appear from the following speciication and from the accompanying drawings, in which- Figure l is a perspective view of the upper portion of an adjustable stool embodying my invention.

Fig. 2 is a horizontal section through the rim at the top of the stand of the stool. taken from the lower edge of the inwardly directed flange of this ring.

Fig. 3 is a fragmentary and enlarged vertical section through supporting portions of Y the stool, taken along the correspondingly l numbered line in Fig. 1.

Fig. 4 1s a section similar to the lower Specification of Letters Patent.

Patented Nov. 2, 1920.

serial No. 375,458.

portion of Fig. 3, but taken at right angles to the latter.

Fig. 5 is an enlarged section of the lower portion of Fig. 3, takenV alongthe correspondingly numbered line of that figure.

Fig. 6 isan enlarged perspective view showing the two portions of the sliding member which release the latching members when the seat is to be lowered.

Fig. 7 is a separate view of the spring which normally holds the latching members in their operative position.

Fig. 8 is a perspective view of one of the latching members.

W'hile my invention may be employed with stools or chairs constructed of .various materials, it is particularly applicable to a metal construction and is therefore shown in the accompanying drawings in such an embodiment. These drawings show the upper part of a stool which includes in its base or stand portion legs l supporting a metal ring 2, which ring desirably has an inwardly directed flange at its upper end to give it a more finished appearance. Rigidly secured to this ring, which is disposed in a substantially horizontal plane, are a pair of spanners 3, each of which has both of its ends e formed into feet contacting flatwisey with the ring 2. These metal spanners have their opposed center portions formed into semicylindrical parts 5 and are desirably secured to each other at opposite sides of these semicylindrical portions by any suitable means, such as rivets 6. Y

Threaded into the cylindrical portion thus formed by the two semicylindrical center parts of the two spanners is a tube 7 which serves as a guide for the stem 8 of the seat member of the stool. This stem 8 is rigidly fastened by any suitable means (which need not here be shown) to the seat 9 of the stool, and is equipped with a series of peripheral grooves which desirably are uniformly spaced longitudinally of the stem. These grooves contract the lower and desirably longer portionof the stem to a series of stem parts 9 of considerably smaller diameter. each of which is spaced from the contracted stem part below the same by a frusto-conical part l0 surmounting a cylindrical portion 11. In other words, the grooves produce the effect of a thinner stem carrying a series of spaced enlargements which slidably fit the these enlargements has a lower squared end the bore of the sleeve 7. Nithin this pocket `l dispose a lpair of latching members 13,

each of which desirably consists of a sub-V stantially arcuate casting havinga groove on its laterally outward face and having one end chamfered and recessed. Seated in the lateral grooves on the two. latching elements V13 are the Varms of a spring 1l, which arms desirably are bent permanently out of alinement with each other when the spring is manufactured (as in Fig. 7) thereby affording a bend which will cooperate with the. relative angular disposition of adjacent parts4 of the latches in preventing the spring from rotating about the axis of the said vertical stem.

Moreover, these latching elements have the l ,center portions of their opposed faces curved along lines combining to afford an opening smaller than the cross'section of the con tracted stem portion 9 andhave these inner face vportions flared downwardly and outwardly as shown by the representation of one of these parts in Fig. 8..

.rt one end, these 'latching members are desirably so Vshaped as to 'abutagainst each other only along the extreme upper edges after the manner shown in Fig.V 5, so that they will rock on each other about this edge point A when they are spread apart against the pressure of the spring 14 or are forced toward each other by the action of this spring. To provide for spreading them apart, l bevel each of the latching elements 13 at its other end along surfaces diverging Vdownwardly as shown in Fig. l and also provide the extreme upper end of the bevel portionwith a recess 15 as shown in Fig. 8. These recesses in the two latching parts co-v operate in affording room for Athe upper shank portion 16 ofa releasing member which also includes a `plate 17 disposedbe tween the said beveled ends and adapted to sped the latter when theV said Vplate is moved vertically upward. .The resulting cam action will be evident from Fig. 4l, which ligure also shows that the same cam veffect due to the beveling of the latching ends will cooperate with gravity and withy the contractile pressure of the spring Min normally returningthe spreader plate 17 to its position of Fig. 4. To move the spreader plate upwardl l provide means accessible from outside the casing vin which 4the latching elements are housed, as for exampler by providing a shank 18 threaded into the plate 1? and carrying a push button 19 at its lower end, T his shank 18 extends through a suitable aperture in the cap 12, while the shank 15 projects through a corresponding aperture in the annular flange which connects the enlarged bottom end of the guide sleeve to the main portion of the latter.

ltlith the part-s thus arranged, it will be obvious from llig. 3 that the latching members rest slidably upon the bottom of the cap 12 which is supported by the guide sleeve 7 in a stationary position; also, that the spring lll will normally approach these latching elements to cause their upper faces to underhang oneV of the shoulders 2O on the stem of the seat member'. Consequently, this stem is normally supported by the lat-ching members, although free to rotate about its own axis. @n lifting the seat, the stem is fraisedwith it, whereupon the engagement of the frusto-conical or tapering stein portions 10 with the beveled inner faces 21 of the latching members Vspreads the latter apart and permits the stem to beraised as much as desired. vThen on releasing the hold on the seat, the spring 14; snaps the latching members back into the nearest groove'of the stem, thereby renewing its support ofV the latter in the new position.

lf the seat is to be lowered, it can readily be held by one hand against too sudden a descent, while the releasing member is lifted bv an upward pressure on the button V19.

vrlflhis spreads the latching elements against the action ofthe spring, as shown by dotted lines in Fig: 5, thereby permitting the enlargements on the stem to clear thelatching members until the seat has been lowered to the desired extent. The upward pressure on the button 19 is then released, whereupon the cam action of the beveled ends of the latching elements cooperates with gravity in returning the re easing stem to its normal position of Figs. 3 and 4, while the spring 14E causes the latching members tof approach each other and underhang one of the shoulders 2O on the stem of the seat member.

ln practice, such a lowering of the seat .to any desired extent can be effected almost in: stantly, particularly fas `the lifting of the button 19 is an exceedingly simple operation. Moreover, since the guide tube 7 is Vstationary while the shank 16 of the releasing member extends through a perforation in the enlargement of this tube, and since the extension 18 to this shank is threadedly ing the button 19 of an incomplete circularV form having one edge cut away and adapted to come close to the enlargements on Vthe stem, l vdispose this :button so `thatit will engage the stem in case of any rotationalV tendency thereof, and therefore prevent it from accidentally unscrewing, it being screwed into position originally while the stem is drawn up entirely into the guide tube. j

By using the two latching elements of such an arcuate form as to combine in corresponding jointly to an incomplete ring approaching the bore of the enlargement on the guide tube I am able to providev a considerable range of opening movement for these elements, while also permitting them to afford a bearing of considerable size for the adjacent shoulder on the stem which is immediately above the latches.V I can therefore employ my construction without using a guide tube enlargement of a clumsy size or highly expensive construction. Moreover, the spreader plate 17 automatically prevents the latching elements from rotat ing within their housing, so that I do not .require any special formations for this purpose, nor do I require any pivot pins or the like in connection with these latching elements.

To secure a good bracing effect for the spanners 3 while also distributing the connections from them to the ring 2 with uniformity, I desirably turn the feet on both ends of each spanner in the same direction circumferentially of the ring 2, and desirably space thefastening rivets 22 at four equidistant points along this ring. I'Iowever, I do not wish to be limited to these or other details of the construction and arrangement here disclosed, it being obvious that the same might be modified in many ways withous departing from the spirit of my invention.

I claim as my invention:

l. In an adjustable stool or chair, a supporting member including a vertical tube, a seat member including a multishouldered stem extending through the said tube, a pair of arcuate latches mounted in the tube and movable laterally of the tube into and out of engagement with an adjacent shoulder on said stem, spring means continuously urging the latches into such engagement, and single digitally operable means for moving the latches out of such engagement and for preventing a rotation of the latches about the stem.

2. A stool orchair as per claim l, with coperating formations on the spring means and the latches for holding the former in operative position.

8. In a stool or chair, a supporting mem ber having a vertical tube enlarged at its lower end, a perforated cap threaded on the said end of the tube, a seat member including a multi -shouldered stem extending through the said tube, latching means within the enlarged end of the tube for engaging with a shoulder of the stem, and single means for releasing the latching means and for preventing the cap from unscrewing.

l. A stool or chair as per claim 3, in which the said single means comprise a vertically slidable member having an enlargement engaging the latching means and having a digitally operable head.

5. A stool or chair asV per claim 25, in which the latching means include a pair of relatively movable members having' opposed diverging ends, and in which the said single means comprises a slidable stem having an enlargement engaging the said diverging ends and adapted to force these ends apart upon slidable movement of the stein.

6. Means for supporting the multishouldered vertical stem of a stool or chair, co1nprising a tube through which the stein eX- tends, the tube having at its lower end an enlargement connected to the main part of the tube by a horizontal collar, a perforate cap threaded on the lower end of the said enlargement, latching means supported by the cap for engaging an adjacent shoulder on the stem, and means extending slidabl i through alined perforations in the said collar and cap for releasing the latching means.

7. A stool or chair support as per claim 6, in which the said slidable means comprise two elements threaded into one another and in which one of these elements is kept from rotating by engagement with the bore of the said enlargement.

8.- A stool or chair support as per claim 6, in which the shoulder-engaging means are freely movable on the cap and are retained in operative position by the slidable means.

9. In a stool or chair having a stem depending vertically from the seat thereof, a supporting member including an upper hori zontal ring, a pair of spanners each secured at both of its ends to the ring, a vertical tube clamped at its upper end betweenthe spanners, and means carried by the tube at the lower end thereof for engaging the stem to support the latter.

l0. In a stool or chair having a stem depending vertically from the seat thereof, a supporting member including an upper ring, a pair of spanners eachsecured at both ends to the ring, the said spanners having medially thereof opposed semi-cylindrical portions, a tube threadedat its upper end into the cylinder formed by the said opposed portions, and means carried by the tube for engaging the said stem to support the latter. 1l. A stool or chair construction as per claim 9, in which each of the spanners comprises a pair of legs connected by a short semi-cylindrical portion, the legs extending substantially at right angles to each other and the two spanners being secured to each other substantially at the junctures of their legs with their arcuate portions.

12. A stool or chair construction as per Vclairn 9- in which each of the spann'ers conisubstantially at right angles to each other,`

the two spanners being secured to each other at opposite ends of their semi-cylindricalV portions, and all of the legs havingl feet secured to theosaid ring and extending in the same direction circumferentially of' the latter.

13. A. stool or chair Construction as per claim 9, in which each of the spanners coni-p prises a pair of legs connected by .a short semi-cylindrical portion, the legs extending substantially at right angles to each other the two spanners being secured to each other substantially at opposite ends of 'their semi-cylindrical portions 'and' the tube being threaded into the cylinder formed jointly by the semi-cylindrical portions of the two spanners.

14. The combination with a chair or stool seat having a depending mul'ti-grooved stern, of a supporting member including an inwardly flanged vcollar through Which the said stem extends; a pair of arcuate latches housed by the collar and supported by a flange thereof and movable from positions in which both enter one of the grooves on the stem to positions in which they are separated suiciently to clear the stein, the latches Yabutting against each other at one end and having their other ends beveled on converging planes; releasing means extend ing through the collar substantially parallel to the stein and engaging the said beveled Y ends7 andspring nie-ans continuouslyv urging the latches toward the stern. Y

15. A stool or chair construction as per claim lll, in which each latchis grooved on its outer face, and in which the .spr-ing is biturcated and has its arms seated respectively in the grooves oi the two latches and converging from eachother at their juncture, whereby the said converging prevents the l,spring from moving-peripherally of the Y latches. y

Signed at Chicago, lllinois, Aprilv 17th? HARRY SHAW.- 

